Lawnmowing is a funny gimmick to add, and the rewards are good but its far too grindy to expect your average player to get it without grinding for hours on end. Forcing people on top of that to refuel it, or to get a unlimited fuel upgrade would just be adding an arbitrary hurdle on top of it all. The unlimited fuel upgrade is underused as is because there are plenty of sources of movement aside from buggy, laggy cars but still that shouldn't be a leading reason as to why it should for some reason be added to lawnmowers in my opinion.
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